Experience Quality and Care with GMK Business Group

Welcome to GMK Business Group, LLC, home of Grandma Mattie’s Catering and our trusted automotive sales division. We proudly serve the Antioch, CA community with two essential services built on integrity, quality, and genuine customer care.

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Our Unique Services

Explore the exceptional offerings at GMK Business Group, LLC.

Catering Services – Grandma Mattie’s Catering

Experience delicious, home-inspired meals crafted with care and tradition. Our catering services are perfect for family gatherings, corporate events, celebrations, and special occasions of any size.

Automotive Sales – Reliable Vehicles You Can Trust

Our automotive division provides dependable, well-inspected vehicles at fair and transparent prices. We focus on offering cars that fit your lifestyle, budget, and driving needs—without the pressure or hidden fees you find elsewhere.

Customer-Focused Support

Whether you're planning an event or searching for your next vehicle, our team is here to guide you every step of the way. We pride ourselves on honest communication, personal attention, and service that treats every customer like family.

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Your Trusted Partner in Quality

At GMK Business Group, LLC, we are dedicated to elevating your experiences through two core passions: exquisite catering and reliable automotive solutions. Founded by George Young, our Antioch, CA-based company embodies integrity, exceptional value, and personal care. From Grandma Mattie's home-inspired meals that foster community connections, to dependable vehicles offered with transparent pricing, we strive to serve our customers with outstanding service, every step of the way.